The present invention relates to filter testing equipment and more particularly to a method and apparatus for comparative testing of at least two successively aligned layers of filter media in a particulate laden fluid stream.
Testing devices for testing the integrity and/or efficiency of filter media are generally well known in the filtration art, attention being directed to such U.S. Pat. No. 3,810,697, issued to S. B. Steinberg on May 14, 1974; U.S. Pat. No. 4,213,768, issued to A. J. Bauman et al. on Jul. 22, 1980; U.S. Pat. No. 4,279,508, issued to H. L. Everroad on Jul. 21, 1981; U.S. Pat. No. 4,387,993, issued to R. J. Adrian on Jun. 14, 1983; U.S. Pat. No. 4,494,403, issued to C. W. Bowers et al. on Jan. 22, 1985 and, Japanese patent publication No. 6,331,114 5A of T. Kazuo on Dec. 19, 1988--all of which teach various efficiency and/or integrity testing embodiments for testing filter media. In addition, attention is further directed to U.S. Pat. No. 5,203,201, issued to M. A. Gogins on Apr. 20, 1993; U.S. Pat. No. 5,244,480, issued to H. G. Henry on Sep. 14, 1993; and, U.S. Pat. No. 5,488,811, issued to J. Wang et al. on Feb. 6, 1996--these three patents teaching filter testing arrangements which include structure for testing filter media in more than one position in a filtration system. Finally, attention is directed to MKS Instruments, Inc., Bulletin (cover pg. and ppgs. 14, 20 and 73). However, none of these aforementioned patents and bulletin even recognizes, let alone teaches, the importance of a comparative testing sample of at least two aligned filter media samples to be preselectively relatively positioned and/or spaced in aligned relation in the same filter testing system including a multi-stationed filter media sample holder. The inventive, unique and novel comparative filter media testing arrangement as disclosed herein, which allows for the control of differential pressure flow through filter media to be tested selectively maintaining the pressure drop across tested media substantially equal by varying media characteristics and spacing between tested media and/or the composition nature of tested media has particular applicability to U.S. Pat. No. 5,968,373, issued to Kyung-Ju Choi on Oct. 19, 1999. In order that appropriate filter media of preselected filtering properties and preselected layer spacing be incorporated in applicant's novel method and apparatus as set forth in the aforementioned U.S. Pat. No. 5,968,373, it is essential that each layer of filter media selected, as well as the relative spacing between layers, be carefully and accurately criteria compliant prior to further manufacture, assembly and subsequent replacement thereof. The novel filter media sample testing equipment as described herein permits the manufacture, assembly and replacement of layers of filter media and the replacement thereof in a straightforward and economical apparatus and method with a minimum of structural parts and with a minimum of operating steps--utilizing readily and variable assembled parts which are commercially and economically available for unrelated uses such as conduit piping. Various other features of the present invention will become obvious to one skilled in the art upon reading the disclosure set forth herein.